Weather Underground midday recap for Tuesday, June 30, 2015

A low pressure system moved across the Midwest on Tuesday, while a ridge of high pressure lingered over the eastern Pacific.

An area of low pressure shifted east northeastward over the upper Midwest. This system ushered showers and embedded thunderstorms over the Great Lakes and portions of the Northeast. A cold frontal boundary associated with this system extended southwestward. This frontal boundary collided with warm, muggy air from the Gulf of Mexico. This interaction resulted in strong to severe thunderstorms across the interior Mid-Atlantic, the Ohio Valley, the Deep South and the Southeast. Severe thunderstorm warnings were issued across a handful of states, including southern Louisiana, southern Alabama, northern Florida, Georgia, South Carolina, eastern Tennessee, northern Kentucky, Ohio and eastern Pennsylvania. Flash flood warnings were also issued in eastern Pennsylvania on Tuesday. Good Hope, Ala., reported 1.50 inch sized hail. Meridian, Miss., reported a midday total of 2.34 inches of rain.

Meanwhile, a cold frontal boundary stretched across the upper Midwest, the central Plains and the northern high Plains. This frontal boundary brought strong to severe thunderstorms to the northern Plains. Mitchell, S.D., reported a midday total of 0.54 inches of rain.

Isolated thunderstorms also fired up over parts of the Rockies as monsoonal moisture surged across the region. High pressure kept conditions relatively clear to the west of the Continental Divide. Temperatures continued to spike 10 to 20 degrees above normal over the interior Northwest. Ontario, Ore., recorded a midday high of 100 degrees.

Temperatures in the Lower 48 states Tuesday have ranged from a morning low of 39 degrees at Leadville, Colo. to a midday high of 108 degrees at Needles, Calif.